1. Field of the Invention
The present invention relates to systems and methods for treating water and preserving bacteria. More particularly, the invention relates to the reduction of contaminants from wastewater and preserving bacteria in a starvation phase.
2. Description of Related Art
Fluidized bed bioreactors are often used to treat wastewater. Granular media containing bacteria may be positioned in a water column and fluidization may be obtained by liquid recirculation or by external gas fed into the reactor. A biomass may form on the granular media. Wastewater may be batch processed by the biomass. Some new wastewater treatment systems rely on activated sludge from operational wastewater treatment systems to form a biofloc or biomass. However, formation of the biofloc or biomass from the sludge may be time consuming and may not allow customization for specific wastewater contaminants. In addition, as bacteria in a biofloc or biomass fall off of the mass and/or die, a system to replenish specific strains of bacteria in the biofloc may not exist.
Bacteria are usually preserved in the logarithmic growth stage since the growth rate of bacteria exceeds the death rate during this stage. The bacteria are usually preserved by lyophillization or by forming compression tablets. These techniques are time consuming, inefficient, prone to contamination, and/or not cost effective.